Altec 290 series drivers

[scott fitlin]

The Eminence tweeter will not be fine enough sounding. Another user on another forum couldnt believe the difference in sound quality when he switched from an Eminence compression driver to a vintage JBL! All the edginess the guy couldnt get of left with the Eminence driver. I have heard the tweeter your talking about and sonically isnt in the same league as your Altecs!

If you need supertweeters, I recommend you find a pair of used JBL 2405,s! These can be found at www.vintageaudiosales.com and ebay from time to time and are much more suited quality and sound wise to your Altec drivers!

[scott fitlin]

1 pair JBL 2405 slots with Alnico magnets available! www.vintageaudiosales.com JBL-3 section.

Some Altec items available as well.

[jnorv]

Scotty, I would be interested in your thoughts on why a 2405 and not one of the other 2400 series. Same basic driver with different dispersion patterns.

JIm N

[scott fitlin]

well, the 2405 goes up to 20K, and has very wide dispersion, 140 x 40 degress @ 10k. This means that you wont hear your highs drop off as you move off axis ( move around your room )and this particular tweeter when crossed over at 8-8.5k has a delicate sounding top end, when used with a small power amplifier! You only need a few watts to achieve good high frequency output with these!

The 2404 Bi-radial has 100 x 100 degree dispersion and can be crossed over as low as 4k but in my opinion, you can hear the plastic bi radial horn! Its a wee bit chalky sounding, but you can get very good results with them, but they dont sound as fine as the 2405 slot!

The 2402 Bullet tweeter! The Most efficient tweeter on earth! 110db 1w@1m! But, narrow dispersion, and 15k top emd bandwidth! Now, used properly, crossed over at 7K, the bullet sounds like it goes up higher than it does, BUT, because it is a narrow dispersion tweeter, when you move off axis the highs drop hard! They are beamy, I know I use 16 in multiples of 4 for commercial use! This tweeter definitely doesnt need much power and I run mine with, your gonna laugh, 12.5 watts per tweeter! 50 watts per 4! And that times 16 makes alot of high end! But, in my honest opinion, for really fine home Hi Fi the beaminess of the 2402 will get annoying! You have to stay in the spot your speakers are focused on to enjoy them. Another thing to point out, is that the Bullet makes the classic " Disco Top End ", ya know, the Tss, Tss, Tss! I would imagine for serious home Hi Fi listening, the exaggerated sizzle is not what you are seeking, but then again, you might like it, too! I think a more open, airy, extended delicate top end would be the order of the day! If you listen to jazz and your listening to a drummer work the high hat with a brush, the slot will give you that golden shimmer, without excess sibilance! another thing to point out with the bullet, is because they direct so much acoustic energy to one position they, besides being a little raspy, can, in home use situations, be a bit overbearing at times! The old JBL literature used to give this definition for its use, " for applications requiering high directivity control, and penetration". So, it will have that Cut Through in a noisy enviroment and a long, narrow throw, with extremely high efficiency, but do you need this in your living room?

Now if you are tri or bi amping, the slot will have the least drop off in your room, and crossed over at 8 to 8.5K will give you top end delicacy with only a few watts and be quite enjoyable as well as noticeably extend your frequency response to beyond audibility!

[scott fitlin]

Oh yeah, even though the magnet structures are the same for all three tweeters, the horns are different, and so are the diaphragms! The 2402 and 2405 each have their own specific diaphragm! The 2405 slot diaphragm being the lightest!

[Rockets]

Thanks guys for the info. I'd been looking for a decent "affordable" pair of the 2404H before I saw the APT-50's. Not knowing how they sounded kept me from placing an order...so I guess I stick w/ the JBL's...will take a look at the 2405's. Crossing at 8Khz brings up a question. Where do the 290's roll off?

Todd, I'll keep that in mind about the custom horns, however, I need to do a little more searching before I go down that road !

Thanks again!

[Rockets]

I just looked at the spec on the Altec 290. Good up to 7Khz. Looks like the 2405 won't do, and will have to stick w/ the 2404H.

[Rockets]

Thanks Scotty, I'd still want to look at a plot on the 290 before I crossed them that close to the end of their range. Appreciate the info.

[scott fitlin]

Well, your not exactly wrong about what your saying! If you go with the 2404 bi radial itll crosover at 7K very well, and has very good dispersion, but, to me, its good, just not as good as the 2405 slot.

[scott fitlin]

I accidentally created a new thread instead of posting my reply in this thread! LOL, its not the first time this has happened to me, but Rockets my post on 2404,s vs 2405,s is for you!

Accidents will happen!